Este manual va desde los aspectos más abstractos (las leyes de Maxwell) a los más concretos (las ondas electromagnéticas). Las primeras son un conjunto de ecuaciones que constituyen un elemento capital de la historia de la física y de la ciencia y la ingeniería actuales. Nos permiten explicar fenómenos tan aparentemente dispares como por qué nos llega la luz del Sol o por qué podemos comunicarnos a través del teléfono móvil. Y en todos estos fenómenos hay presentes unos...

Topics: Physics, Electromagnetism, Electromagnetic radiation, Maxwell's equations

Source: https://openlibra.com/es/book/ondas-electromagneticas-ecuaciones-de-maxwell

Este libro está basado en los contenidos de la asignatura Fundamentos Matemáticos II de la titulación de Ingeniería Industrial y va dirigido, principalmente, a alumnos de primer curso de Ingeniería, tanto de las antiguas titulaciones como de los nuevos grados. Puesto que está pensado como un curso básico del estudio analítico de las ecuaciones diferenciales, abarca los métodos habituales de resolución de ecuaciones de primer orden y el estudio de las ecuaciones diferenciales lineales,...

Topics: Mathematics, Differential equations, Algebra, Algebra linear, Mathematical analysis

Source: http://repositori.uji.es/xmlui/handle/10234/24281

These lecture notes on differential equations are based on the author's experience teaching Math 280 and Math 351 at California State University, Northridge since 2000. The content of Math 280 is more applied (solving equations) and Math 351 is more theoretical (existence and uniqueness) but the author has attempted to integrate the material together in the notes in a logical order and selects material from each section for each class. The subject matter is classical differential equations...

Topic: Differential Equations

Our research during the third final year of funding culminated with 9 papers published [in addition to 4 and 5 papers published in the first and second year respectively], 1 accepted and 5 submitted. Aside from three specific models: Internal Structural Dynamics Model (ISDM), External Shocks Dynamics Model (ESDM) and Mixed Structural Dynamics Model (MSDM, the investigations of Random Mobile Networks and their reliability (within the framework of Network Science) have been concluded with novel...

Topics: DTIC Archive, TEXAS UNIV AT ARLINGTON DEPT OF MATHEMATICS, *NETWORK TOPOLOGY, *MATHEMATICAL MODELS,...

Stability is proven for two second order, two step methods for uncoupling a system of two evolution equations with exactly skew symmetric coupling: the Crank-Nicolson Leap Frog (CNLF) combination and the BDF2-AB2 combination. The form of the coupling studied arises in spatial discretizations of the Stokes-Darcy problem. For CNLF we prove stability for the coupled system under the time step condition suggested by linear stability theory for the Leap-Frog scheme. This seems to be a first proof of...

Topics: DTIC Archive, PITTSBURGH UNIV PA DEPT OF MATHEMATICS, *NUMERICAL ANALYSIS, *EQUATIONS, STABILITY,...

Recently, Parida and Gupta (J. Comp. Appl. Math. v206 (2007) p873-877) used Rall's recurrence relations approach (from 1961) to approximate roots of nonlinear equations by developing several methods, the latest of which is free of second derivatives and is of the third order. In this paper, the authors use an idea from Kou and Li (Appl. Math. Comp. v187 (2007), p1027-1032) and modify the approach of Parida and Gupta to obtain yet another third-order method to approximate a solution of a...

Topics: DTIC Archive, NAVAL POSTGRADUATE SCHOOL MONTEREY CA DEPT OF APPLIED MATHEMATICS,...

This report was developed under a STTR contract for topic OSD10-T001, The goal of this project is to develop advanced large-eddy simulation (LES) software based on a high-order spectral element method on unstructured grid for simulation of high speed turbulent reacting flows. The combustion modeling is via the accurate, pdf-based, filtered mass density function (FMDF) method. In FMDF, the turbulence combustion interaction term is naturally closed and does not require additional modeling. Shocks...

Topics: DTIC Archive, ENABLING ENERGY SYSTEMS INC CROWN POINT IN, *SUPERSONIC COMBUSTION, COMPUTERIZED...

The long-term goal of this research is to improve scientists' understanding of the generation of nonlinear internal tides and waves by stratified flow over sills (e.g,. straits) and shelves and the subsequent evolution of the radiated internal disturbance, with particular emphasis on the role of rotation. The primary objectives will be to connect the generation process with the dynamics of the disintegration of the radiated internal tide into shorter, nonlinear internal solitary-like waves, and...

Topics: DTIC Archive, WOODS HOLE OCEANOGRAPHIC INSTITUTION MA DEPT OF PHYSICAL OCEANOGRAPHY, *INTERNAL...

The long-term goal of this work is to develop a fundamental understanding of the underlying physics of the interaction of nonlinear internal waves (NLIWs) with the continental shelf seafloor over a broad range of environmental conditions. We are particularly interested in how such interactions impact underwater optics and acoustics and shelf energetics and ecology by simulating enhanced bottom boundary layer (BBL) turbulence and particulate resuspension leading to benthic nepheloid layer (BNL)...

Topics: DTIC Archive, CORNELL UNIV ITHACA NY SCHOOL OF CIVIL ENGINEERING, *BOUNDARY LAYER, *CONTINENTAL...

High order path-conservative schemes have been developed for solving nonconservative hyperbolic systems in [32, 7, 6]. Recently, it has been observed in [3] that this approach may have some computational issues and shortcomings. In this paper, a modification to the high order path-conservative scheme in [7], based on the high order finite volume WENO scheme with subcell resolution and utilizing the exact Riemann solver to catch the right paths at the discontinuities, is proposed to improve its...

Topics: DTIC Archive, BROWN UNIV PROVIDENCE RI DIV OF APPLIED MATHEMATICS, *COMPRESSIBLE FLOW, *EULER...

This Coastal and Hydraulics Engineering Technical Note (CHETN) is the second in the Inlet Reservoir CHETN series. This CHETN describes the Inlet Reservoir Model (IRM) interface and setting up an IRM project. Part III of the IRM series presents guidance for application and two example problems. The IRM calculates the time-dependent volumetric evolution of inlet morphologic features such as ebb and flood shoals, and estimates bypassing to adjacent beaches based on user-specified relationships...

Topics: DTIC Archive, ENGINEER RESEARCH AND DEVELOPMENT CENTER VICKSBURG MS COASTAL AND HYDRAULICS LAB,...

The equation of state (EOS) with separable internal energy played a big role in the analysis of dynamics of condensed matter and development of the mathematical basis of the shock-wave physics (Courant, R.; Friedrichs, K. O. Supersonic Flow and Shock Waves; Interscience: New York, 1948). For such models, the internal energy density Epsilon , as a function of the specific volume V and entropy density S , can be presented as Epsilon(V , S) = Delta(V) + X(S), where functions Delta(V) and X(S)...

Topics: DTIC Archive, ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD WEAPONS AND MATERIALS RESEARCH...

Peskin's Immersed Boundary (IB) method is one of the most popular numerical methods for many years and has been applied to problems in mathematical biology, fluid mechanics material sciences, and many other areas. Peskin's IB method is associated with discrete delta functions. It is believed that the IB method is first order accurate in the L(infinity) norm. But almost none rigorous proof could be found in the literature until recently [9] in which the author showed that the velocity is indeed...

Topics: DTIC Archive, NORTH CAROLINA STATE UNIV AT RALEIGH CENTER FOR RESEARCH IN SCIENTIFIC COMPUTATION,...

Electromagnetic Bandgap (EBG) structures exhibit large continuous regions as a function of frequency over which they will not allow a signal to propagate. A subclass of bandstop filters (BSF), EBG structures stop a signal from passing through by having signals not propagate in abeyance of Maxwell's Equations. Typically, EBG performance is achieved by modulating the geometric properties of an electromagnetic-guided or radiating structure so as to create a periodicity which induces the EBG and as...

Topics: DTIC Archive, MACQUARIE UNIV SYDNEY (AUSTRALIA), *ELECTROMAGNETISM, *INTEGRATED CIRCUITS,...

Developed a versatile numerical technique that allows us to calculate the energy, the temporal shape, the spectrum and the phase of an ultrashort pulse propagating in multi-photon absorbing medium with fully realistic spectral shapes and absorption profiles. This approach is based on solving straightforward ODE instead of Maxwell-Bloch type equations, which usually require FTDT calculations. Furthermore, the solver is implemented using 100% commercial software (Mathematica ver. 8) running on a...

Topics: DTIC Archive, NATIONAL INST OF CHEMICAL PHYSICS AND BIOPHYSICS TALLINN (ESTONIA), *COMPUTERIZED...

We introduce a new class of numerical differentiation schemes constructed for the efficient solution of time-dependent PDEs that arise in wave phenomena. The schemes are constructed via the prolate spheroidal wave functions (PSWFs). Compared to existing differentiation schemes based on orthogonal polynomials, the new class of differentiation schemes requires fewer points per wavelength to achieve the same accuracy when it is used to approximate derivatives of bandlimited functions. In addition,...

Topics: DTIC Archive, YALE UNIV NEW HAVEN CT DEPT OF COMPUTER SCIENCE, *PARTIAL DIFFERENTIAL EQUATIONS,...

Dielectric relaxation times were measured for 1,4-polyisoprenes (PI) of different molecular weight. From the data, the number of dynamically correlated segments, Nc, was calculated using an approximation to the dynamic susceptibility. Nc increases with approach to the glass transition in the usual fashion and also increases with increasing molecular weight of the PI. The latter effect is ascribed to the loss of the configurational mobility conferred by the chain ends. The correlation volume was...

Topics: DTIC Archive, NAVAL RESEARCH LAB WASHINGTON DC, *HETEROGENEITY, *MOLECULAR WEIGHT, *SCALING FACTOR,...

This paper presents a depth-averaged sediment transport model with emphasis on morphodynamic processes near coastal inlets and navigation channels. The model solves the depth-averaged two-dimensional non-equilibrium transport equation of total-load sediment, considering bed-material hiding and exposure, avalanching and sediment transport over hard bottoms. The model is coupled with a depth-averaged circulation model and a spectral wave transformation model. Predicted bed changes are compared...

Topics: DTIC Archive, ENGINEER RESEARCH AND DEVELOPMENT CENTER VICKSBURG MS COASTAL AND HYDRAULICS LAB,...

Recently, sparse representation has been applied to visual tracking to find the target with the minimum reconstruction error from the target template subspace. Though effective, these L1 trackers require high computational costs due to numerous calculations for L1 minimization. In addition the inherent occlusion insensitivity of the L1 minimization has not been fully utilized. In this paper, we propose an efficient L1 tracker with minimum error bound and occlusion detection which we call...

Topics: DTIC Archive, AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH, *TRACKING, *MATHEMATICAL ANALYSIS,...

In [20, 21, 23], we constructed uniformly high order accurate discontinuous Galerkin (DG) and finite volume schemes which preserve positivity of density and pressure for the Euler equations of compressible gas dynamics. In this paper, we present an extension of this framework to construct positivity-preserving high order essentially non-oscillatory (ENO) and weighted essentially non-oscillatory (WENO) finite difference schemes for compressible Euler equations. General equations of state and...

Topics: DTIC Archive, BROWN UNIV PROVIDENCE RI DIV OF APPLIED MATHEMATICS, *EULER EQUATIONS, COMPRESSIBLE...

This briefing explores the stability of flame-shock coupling in detonation waves: 1D dynamics.

Topics: DTIC Archive, AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE, *DETONATION WAVES,...

A system of dynamical equations is presented that allow micro air vehicle (MAV) or- nithopter designers to match drive motors to loads produced by exible apping wing spars. The model can be used to examine the coupled system-level behavior of brushed DC motors, gear trains, and any number of linkages and exible wing spars. A Lagrangian approach is used to derive the governing di erential equations of motion for a class of or- nithopter drive systems. Methods used to determine parametric...

Topics: DTIC Archive, AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH AIR VEHICLES DIR/CONTROL SCIENCES...

A novel model equation of state (EOS) for hydrocode is suggested. This model is called the delta chi-EOS because it depends on two functions of one variable each. The delta chi-EOS generalizes the classical incomplete EOS like the ideal gas thermal EOS, the van der Waals EOS, and the virial EOS, among others. We demonstrate the incomplete and complete variants of the delta chi-EOS. We also discuss how to recover the functions delta and chi from experimental measurements.

Topics: DTIC Archive, ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD, *EQUATIONS, *SHOCK WAVES,...

Computational results for the response of piezoelectric materials to various excitations are presented. The governing equations are based on a second-order theory of piezoelectricity, which is specialized for the 6mm crystal class. The equations are formulated in a Lagrangian reference configuration. These equations represent the fully coupled nonlinear multiphysics response. Numerical solutions of these equations are first verified using analytical solutions for wave propagation in linear...

Topics: DTIC Archive, ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD, *PIEZOELECTRIC MATERIALS, COEFFICIENTS,...

A flow, wave, and sediment transport model, the Coastal Modeling System (CMS), was applied to evaluate current and sedimentation patterns at Dana Point Harbor on the southern California coast. The permeability of breakwaters is the main interest in the study for the structural integrity and functioning to protect the harbor. Two Acoustic Doppler Current Profilers (ADCP) were deployed in November 2009 to collect current, water level, and wave data inside and outside the harbor. The model was...

Topics: DTIC Archive, ENGINEER RESEARCH AND DEVELOPMENT CENTER VICKSBURG MS COASTAL AND HYDRAULICS LAB,...

In the present paper, we extend Chang's high-order method for system of linear and non-linear hyperbolic partial differential equations. A general formulation is presented for solving the coupled equations with arbitrarily high-order accuracy. To demonstrate the formulation, several linear and non-linear cases are reported. First, we solve a convection equation with source term and the linear acoustics equations. We then solve the Euler equations for acoustic waves, a blast wave, and Shu and...

Topics: DTIC Archive, AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE, *PARTIAL DIFFERENTIAL...

We address the inverse problem for scattering of acoustic waves due to an inhomogeneous medium. We derive and analyze the Hessian in both H older and Sobolev spaces. Using an integral equation approach based on Newton potential theory and compact embeddings in Holder and Sobolev spaces, we show that the Hessian can be decomposed into two components, both of which are shown to be compact operators. Numerical examples are presented to validate our theoretical results. The implication of the...

Topics: DTIC Archive, TEXAS UNIV AT AUSTIN INST FOR COMPUTATIONAL ENGINEERING AND SCIENCES, *INVERSE...

There has been increased interest in the dynamic behavior of sand throughout scientific and engineering communities due, mainly, to its damaging mechanisms against armored military vehicles upon sudden acceleration from buried improvised explosive devices. NASA is also interested in the properties of sand as a stimulant for powdered planetary materials. This thesis focused on developing the experimental techniques to successfully measure its dynamic response to shock impacts. However, sand has...

Topics: DTIC Archive, NAVAL POSTGRADUATE SCHOOL MONTEREY CA, *ARMORED VEHICLES, *DYNAMIC RESPONSE,...

In a multiple-input, multiple-output (MIMO) radar system, two or more transmitters emit independent waveforms, with the resulting reflections received by an array of receivers. Recently, MIMO radar has become a subject of great interest. In part, this interest is due to the potential for MIMO techniques to reduce radar weight and cost, while maintaining performance (as compared with conventional radar approaches). However, the size of these reductions has not yet been quantified. Likewise, a...

Topics: DTIC Archive, MASSACHUSETTS INST OF TECH LEXINGTON LINCOLN LAB, *RADAR, *APERTURES, MODELS,...

Using classical molecular dynamics and the polymer-consistent force-field with charges from the condensed-phase optimized molecular potentials for atomic simulation studies force-field, we have calculated Hugoniot curves for the polymer, poly[methyl methacrylate] (PMMA). In this study, the Hugoniot curve was calculated using the Erpenbeck method, where we studied the sensitivity of the calculation on equilibration time, system size, and chain length care. Through this study, we determined that...

Topics: DTIC Archive, ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD WEAPONS AND MATERIALS RESEARCH...

The quantification of uncertainties is critical when systems are nonlinear and have uncertain terms in their governing equations or are constrained by limited knowledge of initial and boundary conditions. Such situations are common in multiscale, intermittent and non-homogeneous fluid and ocean flows. The Dynamically Orthogonal (DO) field equations provide an efficient time-dependent adaptive methodology to predict the probability density functions of such dynamics. This work derives efficient...

Topics: DTIC Archive, MASSACHUSETTS INST OF TECH CAMBRIDGE DEPT OF MECHANICAL ENGINEERING, *COMPUTATIONAL...

We develop an efficient, Bayesian Uncertainty Quantification framework us- ing a novel treed Gaussian process model. The tree is adaptively constructed using information conveyed by the observed data about the length scales of the underlying process. On each leaf of the tree, we utilize Bayesian Experimental Design techniques in order to learn a multi-output Gaussian process. The constructed surrogate can provide analytical point estimates, as well as error bars, for the statistics of interest....

Topics: DTIC Archive, CORNELL UNIV ITHACA NY MATERIALS PROCESS DESIGN AND CONTROL LABORATORY (MPDC), *BAYES...

Guidance laws are developed to optimally position a relay Micro-UAV (MAV) to provide an operator at the base with real-time Intelligence, Surveillance, and Reconnaissance (ISR) by relaying communication and video signals when the rover MAV performing the ISR mission is out of radio contact range with the base. The ISR system is comprised of two MAVs, the Relay and the Rover, and a Base. The Relay strives to minimize the radio frequency (RF) power required for maintaining communications, while...

Topics: DTIC Archive, AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH DEPT OF AERONAUTICS AND ASTRONAUTICS,...

In contrast to discrete descriptions of fracture, phase-field descriptions do not require numerical tracking of discontinuities in the displacement field. This greatly reduces implementation complexity. In this work we extend a phase-field model for quasi-static brittle fracture to the dynamic case. We introduce a phasefield approximation to the Lagrangian for discrete fracture problems and derive the coupled system of equations that govern the motion of the body and evolution of the...

Topics: DTIC Archive, TEXAS UNIV AT AUSTIN INST FOR COMPUTATIONAL ENGINEERING AND SCIENCES, *BRITTLENESS,...

These briefing charts discuss the theme education to innovate--to improve participation and performance of America's students in the Naval STEM (Science, Technology, Engineering and Math) program and the mobilization of the business community to improve the quality of STEM learning in the United States. Organizational goals and characteristics are discussed.

Topics: DTIC Archive, CHANGE THE EQUATION WASHINGTON DC, *STUDENTS, *COURSES(EDUCATION), *PHYSICAL...

Two codes have been developed to predict maneuvering in a seaway. The first uses a quasi-steady analysis with Fourier decomposition to determine the ship responses and find the optimum path for minimum motions. The second extends the existing body-exact strip theory (UMBEST) to arbitrary paths. Several different controllers, including a model predictive controller with constraint enforcement capability and a back-stepping nonlinear controller with desired stability margins, have been developed...

Topics: DTIC Archive, MICHIGAN UNIV ANN ARBOR, *MANEUVERS, *TIME DOMAIN, *SEAKEEPING, *OPTIMIZATION,...

A fundamental requirement in realistic ocean simulations and dynamical studies is the optimal estimation of gridded fields from the spatially irregular and multivariate data sets that are collected by varied platforms. In this work, we derive and utilize new schemes for the mapping and dynamical inference of ocean fields in complex multiply-connected domains and study the computational properties of these schemes. Specifically, we extend a multiscale Objective Analysis (OA) approach to complex...

Topics: DTIC Archive, MASSACHUSETTS INST OF TECH CAMBRIDGE, *ARCHIPELAGOES, *COASTAL REGIONS, *PARTIAL...

A two dimensional mesoscale atmospheric model is presented based on two systems of dynamical equations, the non-hydrostatic compressible Euler equations and the corresponding hydrostatic system. Both equation systems are discretized with a discontinuous Galerkin method in space and a linear semi-implicit multistep method in time. To cover elementwise polynomial spaces up to order four, exact quadrature rules are used. The method is applied to a terrain following quadrilateral grid. To validate...

Topics: DTIC Archive, NAVAL POSTGRADUATE SCHOOL MONTEREY CA DEPT OF APPLIED MATHEMATICS, *EULER EQUATIONS,...

Naval exercises involving use of military sonars operating in the mid-frequency (MF) band, 1-10 kHz, have been implicated in the strandings of marine mammals, especially beaked whales. Understanding the cause or causes of the greater sensitivity of beaked whales to MF sonar has stimulated much speculation and thought. The suspicion that there is a deep connection to anatomy instigated the project summarized here, namely Mid-frequency sonar interactions with beaked whales. The ambition of this...

Topics: DTIC Archive, WOODS HOLE OCEANOGRAPHIC INSTITUTION MA DEPT OF APPLIED OCEAN PHYSICS AND...

This report describes NavyFOAM V1.0, a computational fluid dynamics (CFD) capability based on Reynolds-averaged Navier-Stokes equations (RANSE) aimed at predicting turbulent single- and two-phase flows around ship hulls. The CFD capability employs a finite-volume discretization that allows use of arbitrary polyhedral elements. The free surface is captured using a volume-fraction method capable of accurately resolving sharp interfaces. NavyFOAM has been developed using an open-source CFD...

Topics: DTIC Archive, NAVAL SURFACE WARFARE CENTER CARDEROCK DIV BETHESDA MD, *COMPUTATIONAL FLUID...

The HIFiRE Flight 5 payload was assessed in the NASA LaRC 20-Inch Mach 6 Air Tunnel. The primary objectives were to determine the boundary layer transition characteristics and the effectiveness trips. Boundary layer profiles were extracted from Navier-Stokes calculations of the flow field, and were used to assess trip heights in terms of typical trip correlating parameters. Leading-edge roughness was well-correlated with the R-bar-star parameter. This correlation was used to extrapolate wind...

Topics: DTIC Archive, AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH AIR VEHICLES DIRECTORATE, *BOUNDARY...

Many Free Electron Lasers (FELs) utilize high current, high energy electron beams. Inevitably, a small fraction of the electrons in the beam will exist outside the core beam; these electrons are referred to as beam halo. The halo electrons will travel down an FEL's transport system with the core electrons; any portion of those halo electrons that intercept transport system components can generate radiation that is harmful to the operating personnel. The amount of shielding that is required to...

Topics: DTIC Archive, NAVAL POSTGRADUATE SCHOOL MONTEREY CA, *FREE ELECTRON LASERS, CATHODES, COMPUTER...

The long-term goal of this research is the development of accurate, fast, and advanced statistical and dynamical nonlinear models of ocean surface waves based on first physical principles. These wave models will improve both long-term ocean surface wave forecasts and the prediction of strongly coherent events, such as freak waves, tsunamis, and wave breaking. The objectives of this project are as follows: (1) finding a physically correct wind input term for the Hasselmann equation, (2)...

Topics: DTIC Archive, WAVES AND SOLITONS LLC PHOENIX AZ, *AIR WATER INTERACTIONS, *FORECASTING,...

The deflection limitations of electrostatic flexure-beam actuators are well known. Specifically, as the beam is actuated and the gap traversed, the restoring force necessary for equilibrium increases proportionally with the displacement to first order, while the electrostatic actuating force increases with the inverse square of the gap. Equilibrium, and thus stable open-loop voltage control, ceases at one-third the total gap distance, leading to actuator snap-in. A Kalman Filter is designed...

Topics: DTIC Archive, AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING AND MANAGEMENT,...

In this final report we provide a detailed account of how to call the subroutines of the Mutation library in the context of a practical computational fluid dynamics (CFD) application. The subroutines which were documented in the previous report are shown how to be called in a detailed, step-by-step fashion, from computation of the thermodynamic properties to the transport properties. Specific emphasis is given to integrating the Mutation library with external CFD solvers provided by the user....

Topics: DTIC Archive, VON KARMAN INST FOR FLUID DYNAMICS RHODE-SAINT-GENESE (BELGIUM), *COMPUTATIONAL FLUID...

Lunge feeding by rorqual whales (Balaenopteridae) is associated with a high energetic cost that decreases diving capacity, thereby limiting access to dense prey patches at depth. Despite this cost, rorquals exhibit high rates of lipid deposition and extremely large maximum body size. To address this paradox, we integrated kinematic data from digital tags with unsteady hydrodynamic models to estimate the energy budget for lunges and foraging dives of blue whales (Balaenoptera musculus), the...

Topics: DTIC Archive, BRITISH COLUMBIA UNIV VANCOUVER DEPT OF ZOOLOGY, *WHALES, *HYDRODYNAMICS, *FEEDING,...

Despite being a canonical example of quantum mechanical perturbation theory, as well as one of the earliest observed spectroscopic shifts, the Stark effect contributes the largest source of uncertainty in a modern optical atomic clock through blackbody radiation. By employing an ultracold, trapped atomic ensemble and high stability optical clock, we characterize the quadratic Stark effect with unprecedented precision. We report the ytterbium optical clock's sensitivity to electric fields (such...

Topics: DTIC Archive, MASSACHUSETTS INST OF TECH CAMBRIDGE, *ATOMIC CLOCKS, *OPTICAL PROPERTIES,...

The oxygen reduction reaction (ORR) is an important process in many fields, including energy conversion (fuel cells, metal air batteries), corrosion, and biosensing. For fuel cells, the cathodic oxygen reduction is a major factor limiting their performance. The ORR can proceed either through a four-electron process to directly combine oxygen with electrons and protons into water as the end product, or a less efficient two-step, two-electron pathway involving the formation of hydroperoxide ions...

Topics: DTIC Archive, AIR FORCE RESEARCH LAB TYNDALL AFB FL MATERIALS AND MANUFACTURING DIRECTORATE,...

Bioluminescence represents an operational threat to naval nighttime operations because the flow field associated with their motion stimulates naturally occurring plankton. In the littoral, the primary sources of bioluminescence are dinoflagellates, common unicellular plankton that are also known to form red tides. Dinoflagellate bioluminescence is stimulated by flow stress of sufficient magnitude to cause cell deformation, such as in the boundary layers of swimming animals, in separated flow of...

Topics: DTIC Archive, NAVAL SURFACE WARFARE CENTER PANAMA CITY DIV FL, *BIOLUMINESCENCE, *COMPUTATIONAL...

We review four paradigms of tropical-cyclone intensification that have emerged over the past five decades, discussing the relationship between them and highlighting their positive aspects and limitations. A major focus is on a new paradigm articulated in a series of recent papers by ourselves and colleagues. Unlike the three previous paradigms, all of which assumed axial symmetry, the new one recognizes the importance of rotating deep convection, which possesses local buoyancy relative to the...

Topics: DTIC Archive, NAVAL POSTGRADUATE SCHOOL MONTEREY CA DEPT OF METEOROLOGY, *BOUNDARY LAYER, *TROPICAL...